Electric windshield wiper



l March 2, 1954- c. R. Boo'rHBY ETAL 2,670,492

ELECTRIC WINDSHIELD WIPER Filed March 5, 1948 2 Sheets-Sheet 1 March 2, 1954 c, R, BOOTHBY ETAL 2,670,492

ELECTRIC wINDsHIELD wIPER Filed March s, 194e 2 sheets-sheet 2 /f/m//NWBY BY ,Panne/CK JERRETT tures in the body into the bearing member 30. As the shaft 28 is rotated by means of a crank 3l attached thereto at its inner end and cooperating with a motor means, hereinafter to be described, the pivot 24, the arm V22 and the blade 2l) move in an arc over the surface of the glass of its respective windshield, the arc subtending an angle of approximately 100 having its center at the pivot. This construction may vary considerably and is well known in the art and need not be described in further detail.

The position of the pivot with reference to its cooperating windshield section is such that the blade 26, as oscillated by the arm 22, may sweep an angle of approximately 160 over the glass as measured from the bottom edge i8 thereof,- against which the blade 2B is adapted to rest when in parked position, being mounted in an angular relation with the arm 22 for this purpose when the arm extends outward relative to the body strut it. The arms 22 are arranged, so that they oscillate in the saine direction with reference to each other, namely, will move inwardly toward the strut i6 together and move outwardly together. The extreme outward position is the parked position, which is obtained by a cooperating mechanism which will be described hereinafter.

For convenient use on a mass production line. the Divot bearing members 30 are held in spaced relation to cooperate with spaced apertures 32 in the body member l by means of a bracket 38 offset portion 36, to which is attached an electric l motor 48 by a stirrup 5U, which is resiliently mounted on the portion l by bolts 52, extending through rubber grommets 5d and threading into the stirrup Et. The resilient mounting tends to reduce transmission of motor noises to the bracket and possibly to the body member IB, to which the bracket is attached to hold the complete sub-assembly in position on the automotive vehicle.

The stirrup 55 for the electric motor 48 is preferably attached to a eld member 56 by welding or the like, the field member being provided with pole shoes 58 cooperating with field coils 60 in a well known manner. The pole shoes 58 are attached to the field member 56 by means of screws 62. In Fig. 3A, a modification of the stir- A pair of bolts 8G (Fig. 2) are provided to draw up the end heads on the field member by extending longitudinally thereof and being threaded into the end head M. Indexing means, comprising pins 82, fitted on each end head, are provided to cooperate with slots B on each end of the iield member, being preferably located adjacent one of the bolts Sii, as is best shown in Fig, 6. The indexing means predetermines the angular relation between the end heads by locating from the cooperating eld member.

The inner side of the end head i6 is provided with a pair of brush holders S5 and 86 to house spring-biased brushes 88 which cooperate with the commutator S6 in a well known manner, it being unnecessary to describe them in further detail. Brush holder 85 is attached to and insulated Iby a ber plate 9D attached to the end head 16 by rivets 92, while brush holder-86 is grounded to the end head as shown. Y

Each of the end heads 14 and I6 is provided with an integral housing Sli and for housing a Sear s6 in its cavity 93 to cooperate with the worms 'i6 on the ends of the armature shaft 68, which is adapted to extend into the cavity 98 thereof. The armature shaft is provided with a pair of shoulders 99 which are adapted to cooperate with spring members lil (Figs. 3 and 5) which provide a resilient end thrust thereto and are attached to the ends heads 9d and 95 by rivets ll, The springs Iii!) are slightly deflected to bear against the shoulders 99 to prevent excessive endwise movement of the shaft and prevent noisy bumping should the forces acting against the shaft become unbalanced. The normal end thrust on the shaft arising from the cooperative relation of the gears 9G with their wormsv 7B is balanced and tend to counteract each other. Referring to Fig. 3, the thrust of the gear on the left side of the motor tends to move the shaft to the right, while the thrust of the gear on the right side of the motor tends to move the shaft to the left, so that these thrusts, being opposed, will balance each other and thereby reduce the friction losses in the motion-transmitting devices. rlhe overall efficiency of the windshield wiper is materially enhanced thereby.

rup El! is shown, wherein the embracing member from each end of the armature, being provided at f 1 each end with a worm 'i6 integrally formed therein. The armature shaft is journaled in selfaligning bearings 12 positioned centrally by holders 13 in a pair of end heads 'It and 'I5 fitted into the ends of the cylindrical eld member 56, and 1 centered therein by a shoulder 'I8 fitting snugly Vinto theeld member. Oiling wicks 'I9 are provided for the bearings. I

In Fig. 3B, a modification of the spring |00 is shown comprising a cantilever spring lila which resiliently bears against shoulders t9 to prevent bumping, being attached to the end heads by riveting, the same rivet also attaching the 4bearing holder 13.

The gears 9eare rotatively mounted in the cavities es of the housings es and et by short shafts H32, journaled in hollow bosses I and IBB integral with the housings 9d and 95, being provided .with bearing bushings N8 of the porous, oil- .absorbent type. The gears are fixed to the shafts by dogs lili held on by nuts l l2 threaded on the shaft.

128 of the pivots 24 serving the separate windshield sections l2 and I4, in order that links H4 which connect the arms 3710i thepivot shaft 28 maymovein a planeI when actuated by arms it It. fiiredlyfmounted orrthe shafts ft2. `Studs |4 |-8' arel riveted into the ends of lthe armsA 32T and I respectively asis shownin-Fig. 8f, and extend through an enlarged aperture inthe ends ofv thelinks` I 4l, being provided with arubbergrommet |22 seating-abearing bushing |-`2l tted to thestudl.- Thez assen-iblyis lockedbya spring clin|2'|`f"iittingvv inter-an annular slot |281 inthe stud:

Returning now to thel housings-911 and 95'-, their cavities 98, in which the gears. SG1-and their coop-- erating Worms 'mare mounted, are closed by covers iittedL `by' screws |32 'to the open1 face |34 of the-housing, beingprcvided with gasket |36 `tohold greasein Vthe cavities tforlubricating-'the-moving parts. Similarcovers may be provided for e'achhousing if desired.. If, how-V ever; a-motor-parking-switch is tobea-provided, it1is=-convenientlymounted on one of thesecovers, asfisrshown in Fig. 4.-

Should' theV parking switch be desirable, it is mounted on aspecial cover platefillilg'v which is pierced by a flanged-aperture |42, in which is mounted' a headed-v push buttonl-llV of insulating materiali The head of nthe pushbutton HiS- isv positioned eXteriorly of theplate Mt'and itsstem M5 -extends into the cavity 98 of' the housing t5 andrv cooperates -witha cam rise |43 positioned on'the forward 'facef of 4'the `gear* 96A, asv seen in Fig? 9; ThepushA button IM isithrust toward the-gear by leaf spring itil', mounted in arl-insu'- lated pile |52 on the plateV |40. The' leaf spring Huis-provided witha Contact its, cooperating withrarseoond contact ld-'adjustably mountedY on the Aend-*of a-shoi'ter leaf spring i555, also mounted in the insulated4` pile |52. When the cam rise Muthruststhe push button ist outwardly, it will` disengagethev two contacts` its' and |54 --to openthe rnotorV circuit andVV park the wi'perarms 22-'at apredetermined position,prei-` erablyI when" parallel to the vbottomedge s it of the-windshield"sectionsV |2' and i4.

lGonductors 15S' are provided to complete the circuitsfrom the switching mechanism to the motor.v An outer cover |60 is provided to house therswitching mechanism, being YheldinY position by"screws^|"32 already described; Conductors lii enter thefcover |60 bya 'rubber' insulating groinmet'fl62`- and enter4 the motor' casing in asimilar manner; as .is-well known in the art."

' Inh the schematic diagram of connections shown inlilig. 10; a source of' electrical energy B is con*- nectedto the ignition switch I, thence tok parallel circuits having in one branch a manual. control switch M and` in the other branch thel cam-operated' switch cooperating'with the motorincluding contacts |53 and '|54, both parallel circuits leading tothe field F andY armature of the motor as shown; A' resistance R may be provided if desired. The source Bythe' armature A,V and4 the eldF are all grounded as shown to complete the circuits: From the circuit, it is clear that the manual switch M controls the operating circuits of the motor. When, however, the manual switch M is: opened;w the cam-operatedswitch, including contacts |53 and |54, maintain thefoperating circuit closed until opened by the cam Hi8 which will bein timed relation with the movement of the-arms 22 when-they are in" parking position. If parking isnot desired, the manual switchv M used1 alone.

For assemblyV on -amotor vehicle, the `bracket 3.8"has assembled thereon the motor at a-'central location and the twofpivot shaftsengaging the endsof rthe arms, the-assembly--bei-'ng thenrplaced asa unitunder the dash with'the bearing heus-'- ings-*30 and their shafts 23r extending throughapertures 32 in the cowl. The bracket' isf-then` attached to the frame of the vehicle by' bolts positioned-through apertures Il (Fig. I) and-fthe plates 34 are attached to the bearing housings by screws BB1-which hold them in positionon the cowl. Thereafter the arms 22 with blades: 2`0- are attached! to the shafts 28 by screws ZS'inLtliei-r; proper angular relation to give the. prescribed sweep over the glass of their-cooperatingsections:y This'providesa-convenient assembly means parte ticularly adapted to mass production lines.

Itis to be understood that the above'detailed description of the present invention is intended to disclose an embodiment-to those skilled -in-'the art, but that the invention is-not to be construed as limited in its application tothe details ofi-con struction and arrangement of parts illustratedli-n the accompanying drawings, since the invention is capable of being practiced and carried out in variousy Ways without` departing from the spirit of the invention. The language used in the specication relating to the operation and function ot the elements oi the invention is employed for purposes of description and not of limitation-andit is not intended tolimit the. scope of the follow-ingxclaims beyond the-requirements of'the prior art.

What is claimed:

l. In a windshield wiper, an assembly adapte ed to be applied as a unit to an angularly*ari-.-` ranged or curved windshield of anautomotive vehicle, comprising anattachment bracket-with; a pair of laterally extending arms', motor-means" including a unitary rotary shaft attached to the bracket between the arms, pivot means for the wiper attached to the ends of the arms and heldin angular relation normal to the adjacent sec-c,i tions of the windshield, crank means on. eachot the pivot means, links connected to eachof the crank means extending toward the motor; and motion translating means includinggearsxco-e operating with each link in .the plane of move` ment of the pivot arms, said gears being rotate ably affixed, one to each end of .the motor casing, said shaft. of the motor means being positioned. between the motion translating means'. and. co'.- operating therewith at eachof. its ends byrneans of an integral worm. engaging the. respective gears at' an oblique angie, the relationzbetween the gears and worms .being such. that the 4end' thrust of the worms on the driving shaft duringv driving relation counteract and balance eachother.

2. In a driving means for a dual windshieldwiper for use with sections of a non-planar windshield, an electric motorv comprising a tubular field member and. a rotatable armature including. a unitary rotary shaft mounted therein, end' heads for the field member including. journal means for the ends of the armature shaft,..i`n. tegralworms positioned on each. of the ends ofthe` armature shaft adjacent the end heads, reduction gears cooperating with each worin -journaled in a portion of the end headsl at-a prevnr determined oblique relation with the axisofthe armature shaft related tothe sections of the non-planar windshield, crank means cooperateing with each of the gears to rotate therewithi under the action of the worms, the reduction gears and the worms being arranged so that "the endx thrust on the respective worms counteract and balance each other during the driving' relaY tion,'resilient means to cushion the end thrust of the armature shaft, and means to hold the end heads in position on the field member in predetermined relation.

3. In a driving means for a dual windshield wiper cooperating with sections of a non-planar windshield, an electric motor comprising a tubular field member and a rotatable armature including a unitary shaft mounted therein, end heads for the field member including journal means for the ends of the armature shaft, guide means to predetermine the angular position of the end heads with relation to the field member, Worms affixed on each of the ends of the armature shaft adjacent the journal means, reduction gears housed and journaled in integral portions of the end heads and cooperating with each worin at a predetermined oblique relation with the axis of the armature shaft related to the sections of the non-planar windshield, crank means cooperating with each of the gears to rotate therewith under the action of the worms, the reduction gears and the worms being arranged so that the end thrust on the respective worms counter and balance each other during the driving relation, and means to hold the end heads in position on the field member. 4. In a driving means for dual windshield Wiper cooperating with sections of a non-planar windshield, an electric motor comprising a tubular field member and a rotatable armature including a one-piece shaft mounted therein, end heads for the field member including journal means for the ends of the armature shaft, Worms affixed on each of the ends of the armature shaft adjacent the journal means, reduction gears cooperating with each worm journaled in a portion of the end heads at a predetermined oblique relation with the axis of the armature shaft to obtain a parallel relation to said windshield sections, housing means for the gears at least in part integral with the end heads, crank means cooperating with each of the gears to rotate therewith under the driving action of the worms, the reduction gears and the worms being arranged so that the end thrust on the respective Worms counteract and balance each other during the driving relation, and means to hold the end heads in position on the held member in predetermined relation.

5. In a driving means for a dual windshield Wiper cooperating with sections of a non-planar Windshield, an electric motor comprising a tubular eld member and a rotatable armature including a one-piece shaft mounted therein, said .l

motor being in circuit with a source of power, end heads for the field member including journal means for the ends of the armature shaft, worms in spaced relation afxed on each of the ends of the armature shaft, adjacent the outside of the end heads reduction gears cooperating with each worm at the ends of the shaft, said gears being journaled in a portion of the end heads at a predetermined oblique relation with the axis of the armature to establish a parallel driving relation with the sections of the Windshield, crank means cooperating ywith each of the gears to rotate therewith under the action of the worms, the reduction gears and the worms being arranged so that the end thrust on the respective worms on the shaft counteract and balance each other during the driving relation to thereby substantially reduce friction losses in the motor, switch means on one of the end heads for parking the crank means at a predetermined position by breaking the motor power circuit, cam means cooperating with one of the gears to actuate the switch means, and means to hold the end heads in position on the field member in predetermined relation.

6. In a driving means for a dual windshield wiper for a non-planar windshield, an electric motor comprising a tubular field member and a rotatable armature including a one-piece shaft mounted therein extending a short distance from the tubular member, end heads for the eld member including journal means for the ends of the armature shaft, bracket means for mounting the motor including pivots for the windshield wipers, worms integrally positioned Aon each of the ends of the armature shaft adjacent the outer side of the end heads, reduction gears cooperating with each worm journaled in a portion of the end heads atan oblique angular relation with the axis of the armature shaft, housings for the gears at least in part integral with the end heads, crank means cooperating with each of the gears to rotate therewith in the plane of a portion of the non-planar lwindshield under the driving action of the worms, link means cooperating with the crank means to actuate the pivots, the reduction gears and the worms being arranged so that the end thrust on the shaft by the respective worms counteract and balance each other during the driving relation to substantially reduce friction loss, and means to hold the end heads in position on the eld member in predetermined relation.

7. In a device of the class described, a unitary rotaryshaft of a motor provided With worms in spaced relation, longitudinally spaced worm gears in rotatably positioned oblique angular relation with each other and with the axis of the shaft to establish a driving connection with each of the worms to provide a speed reduction, the end thrust of the worms during driving relation balancing each other, and reciprocable driving means driven by each of the worm gears operable in diverging planes having a uniform angular relation with reference to the axis of the shaft.

8. In a driving means for a dual windshield wiper to clean portions of a non-planar windshield, a one-piece rotary shaft of a motor having worms at each end, a Worm gear driven by each integral worm on the ends of the shaft, said gears being positioned obliquely lwith the axis of the worms and parallel to the planes of the windshield portions, the end thrust on said shaft by said worms during driving relation balancing each other, crank means driven by each worm gear, an oscillatable crankshaft for each windshield portion substantially normal thereto for driving a wiper blade thereover through the agency of an arm, and link means connecting the crank means and the crankshafts.

CLINTON R. BOOTHBY. RODERICK L. JERRETT.

References Cited in the le of this patent UNITED STATES PATENTS Coxon Dec. 12, 1944 

